Effect of carbadox on net absorption of ammonia and glucose into hepatic portal vein of growing pigs.
Chronic cannulas were placed into the hepatic portal vein, ileal vein and carotid artery of growing pigs trained to consume their daily allowance of 1.2 kg of feed (16% protein corn-soybean meal basal diet) in a single meal. The average preoperative BW of pigs was 44.7 kg for Trial 1 (three pigs) and 35.3 kg for Trial 2 (seven pigs). In Trial 1, net absorption of ammonia (NH3) and glucose into the portal vein was determined three times at weekly intervals. The net portal absorptions were derived by multiplying the porto-arterial plasma concentration difference of NH3 and glucose by portal vein plasma flow rate estimated with the p-aminohippuric acid indicator-dilution technique. Differences in the net portal absorptions of NH3 and glucose among the three weekly measurements were small (P greater than .05). In Trial 2, the first sequence of net portal absorption measurements was conducted when pigs were fed the basal diet, and the second sequence of measurements was conducted after the pigs had been fed the diet supplemented with 55 ppm of carbadox for 7 d. Carbadox supplementation reduced (P less than .05) plasma NH3 concentration in portal plasma during the 2.5-h to 5-h postprandial period and decreased (P less than .05) net portal absorption of NH3 during the 2.5-h to 4-h postprandial period. Carbadox, however, did not affect (P greater than .05) net portal absorption of glucose. We suggest that carbadox suppresses the production of cell-toxic NH3 by intestinal microorganisms and, thus, reduces the injury and turnover of intestinal cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Yen
J T
JT
U.S. Department of Agriculture, Clay Center, NE 68933.
Pond
W G
WG
D000641:Ammonia / Q000097:blood*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D002218:Carbadox / Q000494:pharmacology*; D005260:Female; D007408:Intestinal Absorption / Q000187:drug effects; D011169:Portal Vein / Q000502:physiology*; D012039:Regional Blood Flow; D013552:Swine / Q000378:metabolism*
D001786:Blood Glucose; D000641:Ammonia; D002218:Carbadox